The present invention relates to a medium transporting mechanism capable of transporting disc-shaped media such as CDs or DVDs and a medium processing apparatus equipped with the medium transporting mechanism.
In recent years, a medium processing apparatus such as a disc duplication apparatus has been used to write data in media such as blank CDs or DVDs or a CD/DVD publisher has been used to write data and performs label printing to prepare and issue media.
As such a medium processing apparatus, for example, there is a known disc processing apparatus equipped with a disc holding mechanism that holds and transports a disc for a processor to write data perform printing on the disc (for example, see Japanese Patent Publication No. 2006-202379 A).
Before processing such as writing data, the discs are accommodated in a stacker in a stacked manner. In this case, since the discs stacked in this manner are accommodated randomly in the stacker, the center location of each disc is readily deviated from the center of each disc picked up by a disc holding mechanism.
For that reason, the disc processing apparatus is provided with a guide, which includes a movable head having a tapered portion gradually narrows toward a tip end thereof, and the guide is inserted into the central holes of discs to align the discs.
Here, a large force is required to move the guide, as the guide is brought into contact with the central holes of the second and subsequent discs, because a load is increased in the discs other than the uppermost disc due to a frictional force or a contact force between upper and lower discs.
In this case, when the inclined angle of the tapered portion with respect to the axis of the guide is made small, a variation of the diameter of the guide with respect to a downward movement amount of the disc holding mechanism is decreased. Therefore, even when the guide is brought into contact with a plurality of discs subsequent to the second disc, the discs are able to be moved with a large force.
However, when the inclined angle of the tapered portion with respect to the axis of the guide is made small, a protrusion size of the guide is increased, thereby reduces the mobility of the disc holding mechanism or increases in the size of the disc processing apparatus.